Washington -LRB- CNN -RRB- -- Narrow passage of a sweeping health care bill by the House of Representatives portends a continuing difficult fight for President Obama and fellow Democrats to get a bill through the Senate and into law .

The House voted 220-215 late Saturday , with 39 Democrats opposed and one Republican in favor , to approve what would be the biggest expansion of health care coverage since Medicare was created more than 40 years ago .

The Affordable Health Care for America Act , or H.R. 3962 , restricts insurance companies from denying coverage to anyone with a pre-existing condition or charging higher premiums based on gender or medical history . It also provides federal subsidies to those who can not afford it . And it guarantees coverage for 96 percent of Americans , according to the nonpartisan Congressional Budget Office .

But turning the bill into law remains uncertain . The Senate must now pass its own version of a health care bill , and Senate Majority Leader Harry Reid of Nevada last week signaled uncertainty over whether that will happen this year .

Once both chambers have passed a bill , a congressional conference committee will merge the two proposals into a consensus version that would require final approval from each chamber and Obama 's signature .

On Sunday , Obama praised the `` historic '' House vote to pass the bill and called on the Senate to `` take the baton '' and complete its work .

`` For years , we 've been told that this could n't be done , '' Obama said , citing the decades of failed health care reform efforts . `` Last night , the House proved differently . ''

The president called the support by many House members `` courageous '' in the face of `` the heated and often misleading rhetoric around this legislation . ''

`` Now it falls on the United States Senate to take the baton and bring this effort to the finish line on behalf of the American people , '' Obama said . `` And I 'm absolutely confident that they will . ''

However , Republicans and an independent senator who sits with the Democratic caucus signaled Sunday that difficulties remain for Obama on his top domestic priority .

Sen. Joseph Lieberman , an independent from Connecticut , reiterated that he would join a Republican filibuster against a health care bill if it contains a government-run public health insurance option after the chamber 's amendment process .

Speaking on `` Fox News Sunday , '' Lieberman called the controversial public option , which is in the House bill and the Senate version being prepared by Reid , an unnecessary provision intended to bring government-run health insurance in the future .

`` If the public option is in there , as a matter of conscience , I will not allow the bill to come to a final vote , '' Lieberman said . He previously has said he wo n't oppose opening Senate debate on the bill despite the public option provision , and he maintained that stance Sunday .

Lieberman 's stance is crucial because the Democratic caucus has the minimum 60 votes to overcome a Republican filibuster . Senate Republicans unanimously oppose the public option , though Sen. Olympia Snowe of Maine has floated the possible compromise idea of a trigger mechanism that would mandate a public option in the future if thresholds for expanded coverage and lower costs go unmet .

The lone House Republican who supported the bill , Rep. Anh `` Joseph '' Cao , told CNN on Sunday he put the needs of his district over the desire of his party .

Cao 's `` yes '' vote ended up being unnecessary for House Democrats , but it gave House Speaker Nancy Pelosi license to tout bipartisan support for the controversial measure .

`` I felt last night 's decision was the proper decision for my district , even though it was not the popular decision for my party , '' said Cao , a first-term representative from Louisiana 's traditionally Democratic 2nd District . `` A lot of my constituents are uninsured , a lot of them are poor . It was the right decision for the people of my district . ''

Cao acknowledged he extracted some White House pledges to help his district deal with the continuing effects of Hurricane Katrina in exchange for his vote . Asked about the reaction of fellow Republicans , Cao said the party 's leaders `` respect my decision , and I respect theirs . ''

Also Sunday , Rep. Mike Pence of Indiana , the chamber 's third-ranking Republican , said on the Fox program that Democrats were ignoring the wishes of the American public by pushing through the huge health care bill .

Pence said the health care bill would raise costs , increase the deficit and lead to a government takeover of the health care system .

`` I think the American people are deeply frustrated with the liberal establishment in Washington , '' Pence said . `` If Democrats keep ignoring the American people , their party 's going to be history . ''

Democratic Rep. Chris Van Hollen of Maryland responded on the same show that the Congressional Budget Office reported that the House bill would reduce the deficit .

Van Hollen chided Republicans for failing to confront rising health care costs harming the U.S. economy during the years they controlled the White House and Congress .

`` We 've had a great system for insurance companies , '' Van Hollen said , citing large industry profits as Americans face what he called unfair practices such as having coverage denied for pre-existing conditions . `` This is a message to the American people ; we 're trying to bring down your costs to help more Americans afford health insurance . ''

The House vote less than an hour before midnight Saturday was full of drama . With eight seconds left in the voting period , Democrats began counting down and erupted in roars when Pelosi declared , `` The bill is passed '' and banged the gavel .

Republican lawmakers stood silently across the floor , some with their arms folded across their chests .

`` Well , it was about what I thought it would be , '' said House Republican Leader John Boehner of Ohio as he quickly exited .

Later , he issued a statement saying the $ 1.2 trillion legislation would add to the country 's `` skyrocketing '' debt .

`` I came here to renew the American Dream , so my kids and their kids have the same opportunities I had , '' Boehner said . `` I came here to fight big-government monstrosities like this bill that dim the light of freedom and diminish opportunity for future generations . ''

Michael Steele , the chairman of the Republican National Committee , released an equally tersely worded statement .

`` Nancy Pelosi and her liberal lieutenants made a lot of promises today to get the votes they desperately needed , '' he said . `` Make no mistake -- the Democrat leadership 's assurances were based on political expediency , not principle . Anyone receiving a promise from Pelosi is guaranteed to be disappointed in the end when their votes are no longer needed . ''

Earlier in the day , Obama met behind closed doors with Democrats to shore up support for the bill , calling it a chance of a generation .

In the run-up to the vote , Republicans and conservative Democrats joined forces to pass an amendment to the bill to prohibit federal funds for abortion services .

It was considered a big win for them and for the U.S. Conference of Catholic Bishops , which used its power -- especially with conservative Democrats in swing congressional districts -- to help force Democratic leaders to permit a vote on the amendment .

The prohibition , introduced by Democratic members -- including Rep. Brad Ellsworth of Indiana and Rep. Bart Stupak of Michigan -- would exclude cases of rape , incest or if the mother 's life is in danger .

The GOP accounted for 174 of the votes in favor of the amendment , with one Republican voting `` present . ''

On the Democrats ' side , 64 voted for the measure , and 194 voted against .

CNN 's Shirley Hung , Brianna Keilar , Deirdre Walsh , Lisa Desjardins and Elaine Quijano contributed to this report .

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House voted 220-215 late Saturday to approve Affordable Health Care for America Act

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39 Democrats opposed act , one Republican voted for it

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Measure now moves to Senate , where support is less certain

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If both chambers pass a bill , committee will merge the two proposals